1. Field of the Invention
The present invention relates to a device for treating soils or road surfaces.
The present invention is based on the state of the art as described, e. g., in U.S. Pat. No. 6,565,281. Further generic devices are known from DE 42 06 994 A1, U.S. Pat. No. 5,741,085, U.S. Pat. No. 5,893,667 and U.S. Pat. No. 2,394,017 A.
2. Description of Related Art
The known devices for treating soils or road surfaces are provided with a working roll which breaks open the soil or road surfaces and thoroughly mixes the soil and road surface material. In the case of hard road surfaces made from asphalt or concrete the road surfaces are milled. The working roll is surrounded by a bell-shaped roll housing which encloses a working space of the working roll, said working space serving as a mixing space for mixing the worked-off soil material with hydraulic or bituminous binders or with water. The hydraulic or bituminous binders or the water are injected into the working space with the aid of a spraying means fixed to the roller housing, wherein a plurality of outlet nozzles of the spraying means on the roll housing are arranged such that they are directed into the working space. The cutting circle of the tools of the working roll has, in operation, a relatively small distance of e.g. approximately 50 mm to the roll housing, wherein the worked-off soil or road surface material is moved past the inside of the roll housing due to the rotary movement of the working roll. It is a drawback that the worked-off material mixed with binders or water can be pressed into the outlet nozzles even at a high spraying pressure or accumulate before the outlet nozzle. In particular after a standstill of the machine there is the risk that the outlet nozzles are contaminated or clogged by set or hardened or dried worked-off material from the working space, whereby the spraying operation may be affected or even completely stopped.
Cleaning of the outlet nozzles is very problematic because of their difficult-to-access position in the roll casing and may require dismantling of the working roll. Dismantling of the the outlet nozzles from outside the roll housing is very complicated since the injection ramp carrying the injection nozzles, which is arranged between the roll housing and the machine frame, is inaccessible or difficult to access.
Cleaning of the outlet nozzles inside the roll housing involves accident hazards, e.g. when cooled bitumen must be melted with an unshielded flame. Further health hazards occur due to the use of solvents.